Can I order duplex Ultramer® oligos? I want to synthesize a sequence of ~126 nt with sticky ends.
We do not offer duplex Ultramer® Oligonucleotides. You will need to order single stranded Ultramers and follow an annealing protocol like the one below.
1. Dissolve oligos in STE Buffer (10 mM Tris pH 8.0, 50 mM NaCl, 1 mM EDTA) or Nuclease free Duplex Buffer (30 mM Hepes pH 7.5, 100 mM KAc) from IDT. The presence of some salt is necessary for the oligos to hybridize. Dissolve each oligo at high concentration (1–10 OD260 units / 100 uL).
2. Mix two stands together in equal molar amounts. If you do not there will always be single stranded material left over.
3. Heat to 94°C and gradually cool. For many oligos this can be as simple as transferring to the bench-top at room temperature. For sequences with significant hairpin potential, a more gradual cooling/annealing step is beneficial; this is easily done by placing the oligos in a water bath or temp block and "unplugging the machine".
4. The resulting product will be in stable, double-stranded form and can be stored at 4°C or frozen at –20°C.